Grace Livingston Hill 
Duskin 

Brilliant and beautiful Carol Berkley suddenly finds herself faced with the greatest challenge of her young life. When an accident befalls her employer, circumstances force Carol to assume authority and take over the company business. As she embarks on her first business trip, Carol determines to prove her capabilities—never dreaming that she would face danger and corruption that would threaten her life!
In the midst of her perils, Carol wonders who she can trust. Certainly not handsome Philip Duskin for, despite what her heart tells her, he appears to be incompetent and untrustworthy. Then, as she is about to be overwhelmed, Carol decides to follow her heart and discovers the meaning of trust—and love.